Overcoming the Limitations of the Morita−Baylis−Hillman Reaction: A Rapid and General Synthesis of α-Alkenyl-β′-hydroxy Thioesters

Acryloyl chlorides, aldehydes, and PhSLi undergo a direct aldol cascade sequence in the presence of MgBr2·OEt2 via in situ derived thioester enolates, which is followed by oxidative elimination to give α-alkenyl-β′-hydroxy thioesters. Overall, the procedure is rapid, efficient, and generally applicable, even to β-substituted acryloyl chlorides, thus providing an alternative to the Morita−Baylis−Hillman reaction with substantially greater synthetic scope and utility.